Here's the thing with products from Twelve South: it's really tough not to like them. A lot. The quality of every single item we've seen from them is truly impressive, and the design aesthetic is always spot on. At the same time, there's often a "do I really need this?" aspect. The company's BookBook line is no different. Previously versions were available for iPads, MacBook Pros, and MacBook Airs. Now, BookBook for iPhone 4 ($60) has joined the family.

As the name implies, the case is made to look like a book—in this case, a particularly small one. It’s made out of really beautiful brown leather, aged to look like a classic. Along the spine there’s some nice gold-embossed features, included the BookBook name and XII—roman numerals referencing the twelve in the company’s name. Opening the cover reveals a wallet component on the left, and a frame for the iPhone 4 on the right. Like most leather products, breaking it in improves the performance. We found the spine to be a little looser after bending it back and forth a few times.

The inner surface is lined with soft fabric, which prevents the phone’s glass back from getting scratched. It slips in through an opening at the top, and is held in place by a small tab with a red ribbon—it looks just like a bookmark. Once in place, the iPhone 4 is pretty well covered. Both of the long edges are covered to the corners. The left side does have a small opening for the side switch, but leaves the volume buttons covered.

On the bottom both corners are exposed, and there are individual openings for the speaker, Dock Connector, and microphone. Along the top, the Sleep/Wake button, noise-canceling mic, and headphone port are accessible. The frame also partly covers the front of the device, coming up to the Home button on the bottom and covering the top bezel with an opening for the earpiece and front-facing camera. One major downside: there’s no hole for the rear camera. To take pictures you have to slide the iPhone 4 up out of the case or remove it all together.

The wallet will be best suited for those who don’t carry too many cards or other items. It has a ID window and two additional pockets stacked above. Twelve South says that it can hold six to eight cards, but that three to four works best. A long vertical pocket is ideal for cash and other extras.

Without a doubt, BookBook is a conversation starter. The practicality of the case is going to vary depending on the person though. Someone who takes a lot of pictures and has an inches-thick wallet probably won’t like it. But for those who want to simplify the contents of their pockets, it may be a very good option. The design is undeniably cool. As such, we offer a limited recommendation.

Updated June 19, 2012: Twelve South has introduced a new color of BookBook for iPhone: Classic Black, pictured above. The body is the same, but the design on the spine has been updated along with the shade of the leather.

Editors' Note: iLounge only reviews products in "final" form, but many companies now change their offerings - sometimes several times - after our reviews have been published.
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